1. Field
This invention relates to lasers and particularly to anamorphic optical systems for use with lasers that output elliptical beams. In particular, various embodiments of this invention relate to anamorphic optical systems that receive an elliptical beam from a laser diode and transform it into an approximately circular output beam that is polarized.
2. Background
The use of diode laser systems for scientific, commercial, and home applications is becoming widespread due to their low cost, efficient operation, and recent increases in output power. For many such applications, diode lasers are viable replacements for larger and more expensive gas lasers. However, diode lasers can have certain technical problems regarding beam quality (e.g., beam shape and polarization) that should be addressed for their most effective utilization. Many laser applications are best performed with a polarized laser beam having a circular cross-section, rather than an un-polarized elliptically-shaped laser beam which is produced by a typical diode laser. Some laser applications require a high degree of beam polarization, for example, exceeding a 500:1 polarization ratio. An anamorphic optical system can be provided to transform the elliptical laser beam into a more circular beam. However, conventional anamorphic optical systems do not produce a polarized laser beam. Instead, beam polarization is accomplished using one or more additional optical polarizing elements, which can cause beam alignment, power loss, beam quality degradation, cost and size issues. Accordingly, the need exists for an anamorphic optical system that overcomes these issues and satisfies technical requirements regarding beam quality.